Method of extracting oil



Patented May 8, 1923.

FRANK P. CROFT, F PHILADELPHIA, PENNSYLVANIA.

METHOD OF EXTRACTING OIL No Drawing. Application filed June 25, 1917,Serial No. 176,836. Renewed. September 12, 1922. Serial No. 587,847.

I '0 all whom it may concern:

Be it known that I, FRANK P. Cnor'r, a citizen of the United States,residing in Philadelphia, Pennsylvania, have invented .a Method ofExtracting Oil, of which the following is a specification.

One object of my invention is to provide a process or method whereby itshall be possible to extract a maximum quantity 1 of oil from bodies inwhich it is contained and at the same time obtain such oil in the purestform ;it being particularly desired that the process shall be of such anature as to result in the production of oil free from substancestending to oncapable of producing a condition of rancidlty.

It is further desired to provide a process having the abovecharacteristics, which shall involve the treatment of the oil bearingmaterial at relatively high temperatures and pressures with a view tofacilitate the subsequent complete separation of the oil from the solidmaterial in whose cells it had been confined.

In carrying out my invention I first wash the material, for example,cocoanut meat or copra, from which the oil is to be extracted, with aview to freeing it of dirt or foreign material with which it may bemixed, and thereafter grind it into grains or pieces preferably varyingin size from about a sixteenth to an eighth of an inch. The washed andcoarsely ground material is then placed in an open kettle evaporatorwhere it is heated to a temperature of about 212 F., for a timesufiicient to completely drive out of it all water or moisture which itmay hold or contain, care being taken to prevent burning.

As an indication of the completion of this step in the process, smallamounts of oil are freed from the material, and while it is still at atemperature in the neighborhood of 200 to 212 F., it is transferred tosteel tanks or receptacles havin preferably a capacity of about one ton0 said material, and in these it is allowed to cool to a temperature ofabout 110 F. On reaching this temperature, the material is ground in aseries 50 of mills to such a fineness that approximately 90% of it willpass through a #100 mesh sieve. Being in the form of a semiliquld, oilymass, it is then pumped to an extracting or filter press where it issubjected to a relatively high pressure, such for example as 2 tons tothe square inch and the expressed oil collected in a suitable manner.

The oil delivered as a result of this operation is of a light ambercolor and of a hlgh'degree of purity. It is then subjected to the actionof a second filter press in order to remove from it any vegetablematerial which may possibly be held in suspension and the final productis a practically colorless, pure oil having little if any tendency tobecome rancid.

By the above described process I am enabled to obtain a maximum quantityof oil from a given body of material and this desirable result appearsto be due largely to the absolute elimination of moisture before the oilbearing material is subjected to the action of the extracting press asWell as to the fine grinding and relatively high pressure at which saidpress is operated. The escape of the moisture is materially aided byreason of the original coarse grinding, for it is thus put in acondition best suited to permit of the escape of the water vapor.

lVhile the high temperature employed renders the oil in the individualcells of the raw material highly fluid, the subsequent fine grindingefl'ectually breaks down the partitions or walls of thev various cellsin which the oil is confined, so that when the resulting semi-liquidmass is subjected to the high pressure above indicated, practically allof the contained oil is expressed.

Obviously the above described method of operation is particularlyapplicable to the kernels of nuts, seeds and other bodies of vegetableorigin, although it may be advantageously applied to otherliquid-containing solid bodies, and I have found by practical experimentand use that the oil obtained by its use is of the highest quality.

I claim 1. The method which consists incoarsely grinding oil-bearingmaterial; heating said material to remove practically all of themoisture therein; grinding said material to a relatively fine form; andthen subjecting said material to a relatively high pressure to expressthe oil therefrom.

2. The method which consists in coarsely 5 grinding a body ofoil-bearing material;

heatin said material to a temperature in the nelghborhood of 212 F untilpractically all of the moisture has been eliminated and until smallamounts of oil are relatively high pressure to express the oiltherefrom.

In Witness whereof I aflix my signature.

FRANK P. CROFT.

